1. Field of the Invention
The present invention relates to an electronic apparatus having a display panel provided with a display screen for displaying information and a light source for backlighting the display screen, and to a display panel enclosure for housing the display panel.
2. Description of the Related Art
In recent years, personal computers (hereinafter referred to as “PC”) have been widely used not only in office but also at home. As one type of PC, the so-called “notebook type personal computer” (hereinafter referred to as “note PC”) is widely known. The notebook PC has a first enclosure that is a main unit having a keyboard on its top surface and a second enclosure that is a display unit having a display panel and coupled to the first enclosure by a hinge member in an openable and closable manner. The second enclosure is opened to be approximately upright on the first enclosure when it is used, and is closed to lie on the first enclosure when it is not used.
The display panel is provided with a display screen for displaying information and a light source for backlighting the display screen. In recent years, as the notebook PCs become more and more various, in more and more cases, either a display panel having a single light source for backlighting the display screen or a display panel having two light sources for backlighting the display screen is selected, whichever is suitable for the type and function of notebook PC, and the selected display panel is disposed in the display unit. When the display panel having a single light source is selected, a circuit substrate, which has a relatively small area on which a light control circuit for controlling the lighting of the light source is mounted, is employed. On the other hand, when the display panel having two light sources is selected, a circuit substrate, which has a relatively large area on which a light control circuit for controlling the lighting of the light sources is mounted, is employed.
In this case, if the circuit substrate having a relatively small area and the circuit substrate having a relatively large area are both disposed in the display unit of the notebook PC, it is necessary to provide a large space for these substrates in the display unit and therefore, it is difficult to meet the demand for reducing the size of the notebook PC with such a structure.
Conventionally, some techniques have been proposed to mount electronic components of different sizes.
For example, Japanese Patent Application Publication No. 2003-60110 proposes a technique for selectively mounting semiconductor chips of different sizes on the surface of a wiring board where a wiring pattern whose structure is elaborated is formed.
Further, Japanese Patent Application Publication No. 3-27985 proposes a technique for realizing an increase in density by providing an opening section at a semiconductor-element mounted portion of a circuit board and housing a semiconductor element in the opening section.
Furthermore, Japanese Patent Application Publication No. 57-71196 proposes a technique of mounting semiconductor elements on the front and back sides of a circuit substrate and connecting the external lead terminal of the semiconductor element on the front side of the circuit substrate with that of the semiconductor element on the back side of the circuit substrate via the same through hole, thereby decreasing the capacitance generated at the external lead thermals as well as reducing the through hole.
Still furthermore, Japanese Patent Application Publication No. 2001-24146 proposes a technique for realizing electrically-balanced connection by arranging two semiconductor chips to be opposite each other via the center line on a circuit substrate in between.
However, in the technique proposed in Japanese Patent Application Publication No. 2003-60110 for selectively mounting the semiconductor chips of different sizes mounted on the wiring board whose wiring pattern structure is elaborated, it is difficult to reduce the space because the size of the wiring board is large.
Further, in the technique proposed in Japanese Patent Application Publication No. 3-27985 in which the opening section is provided at the semiconductor-element mounted portion of the circuit board and the semiconductor element is housed in the opening section, although the density can be increased, this document never mentions a decrease in the space for accommodating semiconductor elements of different sizes.
Furthermore, in the technique proposed in Japanese Patent Application Publication No. 57-71196 for connecting the external lead terminal of the semiconductor element on the front side of the circuit substrate with that of the semiconductor element on the back side of the circuit substrate via the same through hole, it is possible to decrease the capacitance generated at the external lead thermals as well as to reduce the through hole. However, this document also never mentions a decrease in the space for accommodating semiconductor elements of different sizes.
Still furthermore, in the technique proposed in Japanese Patent Application Publication No. 2001-24146 in which two semiconductor chips are arranged to be opposite each other via the center line on a circuit substrate in between, it is possible to realize electrically-balanced connection. However, this document also never mentions a decrease in the space for accommodating semiconductor chips of different sizes.